Electric incandescent lamp



F. SKAUPY ELECTRIC mcmzmscxam mm Jun 26, 1928.

Filed Oct-13, 1922 @SAM I IhVentbr-z Franz Skaupy,

is Attorney.

Patented, June i 26, 1928.

, 1,675,229 UNITED... STATES PATENT fol-Flo A COFBQRATIQN OF NEW YORK. I

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1 Application filed October 13, 1922, Serial No. 594,362,.and in. Germany October 19,,192'1.

My present invention comprises an incandescent lamp of high efliciency and improved characteristics, in which light is emitted by selective radiation.

In accordance with one of the features of my invention, selective transparent radiators are heated by impact or bombardment with electrons to a temperature at which efiicient light emission occurs.

My invention includes certain novel structural features in incandescent lamps, as, for example, the provision of a "positively charged netting interposed between the transparent radiator and the cathode.

The above and other features of my invention will be set forth with greater particularity in the accompanying drawings.

For a better understanding of my in"en tion, reference may be had to the following description, taken in connection with the ac companying drawings, in which Figure 1 illustrates a lamp having a selective radiator and operating by virtue of gas ionization;

Fig. 2 illustrates a lamp operable independently of gas ionization: and Fig. 3 is a detail view of a modified radiator.

The lamp shown in Fig. 1 comprises a sealed bulb 1 containing a rarified gas for example, argon or other rare gas,and provided with a concave cathode 2 of the type used in X-ray tubes. The anode 3 is constituted of a netting of conductive material which is firm .or rigid enough to supportitself. The radiator 4.- is supported upon the anode stem 5 in such .manner as to interpose the reticulated anode 3 between the cathode and the radiator. The radiator 4 consists of a refractory, transparent or translucent material, as, for example, thorium oxide, a surface layer of which preferably is provided with a content of cerium dioxide. Other refra-ctory, transparent materials may be used,

for example rare earth oxide and l boron nitride. The cerium dioxide acts as a coloring agent, which increases the selectivity ofthe radiator for a desired range of radiation. Other coloring agents may be used, for example chromium oxide. Thin metallically colored bodies, as, for example, titanium nitride, may be applied upon the surface of the radiator, or dissolved in a surface layer, or, indeed, in the radiator as a whole. Preferably, the radiator consists of a single crystal. or of a few crystals. 1

When a suitable potential is applied to the 9 snenz'sxaorr, or 122mm, GERMANY, ASSIGNOR T0 ennnnannnncrnrc central ty,

conductors 6, 7, electrons ion .conductors 9, 10 whereby a current for heating the cathode to incandescence may be supplied. The space in the bulb 11 in this case is evacuated to such degree that gas ionization is substantially absent during the operation of the lamp. To reduce space charge,

the cathode 8 is surrounded by a netting or j grid 12 carried by a leadingin conductor 13. The grid 12 preferably surrounds the oathode as an enclosure or cage and is positively charged during operation. The positive potential of the grid ordinarily will be much less than the positive potential of the. anode. The radiator 14 is surrounded by-a reticulated anode 15, both radiator and anode being carrried by a conductor 16. The operation of the device of Fig. 2 is similar to the device described in connection with Fig. 1..

Various modifications of my-invention will suggest themselves. One modification is shown in Fig. 3, which illustrates a plateshaped anode having a conductive frame 17 containing a transparent plate 18, on the surface of which a symbol, represented by the word Osram, has been applied by means of tungsten powder or other suitable black body radiator. As a black body radiatesmore light of a certain wave length than a transparent body per unit of surface, the metallic coating as represented by the word Osram will appear brighter at high temperature than the rest of the radiator.

What I c aim as new and'desire to secure by Letters Patent of the United States is:

1. An electric lamp comprising an envelope, a refractorv transparent bodyther'e- .which through the spaces in saidanode. I

3. In an electronic d' 'harge device, the 'rovision of a target constituted of a re- I ry transparent body.

4. In an electronic discharge lamp, the provision of a lighting body, which 18 subect to electron bombardment, constituted of one or more crystals of thorium oxide.

5. An electron lam com rising a sealed evacuated envelope, t e cat ode ada ted to operate at incandesoence, a grid 0 ectrode surrounding said whos a ga ma said bulb in l-me with the electron stream, which asses. during the operation ofvsaid device rom said cathode throu said anode, said radiator consisting of transparent material capable of selective radiation when subjectedv to electron bombardment.

In witness whereof, I have-hereunto set my hand this 26th day of September, 1922.

, f-FRANZ SKAUPY.

spaces in I anode and a li lit-emitting body mounted in. 

